These data are 15 simulated cohorts for various combinations of concentration-response threshold and hazard ratio necessary for the replication of the analyses in the paper "A Simulation-Based Assessment of the Ability to Detect Thresholds in Chronic Risk Concentration-Response Functions in the Presence of Exposure Measurement Error."  The "true" PM2.5 level used to generate mortality is included in each cohort file.  Various levels of exposure measurement error can be added to this "true" value to replicate the analyses presented in the paper.